The present invention relates to a wrench for holding or turning pipes or other circular objects, that is instantly adjustable and capable of exerting high gripping and turning forces.
Presently available and patented pipe wrenches are adjusted either by screw adjusting jaws, or by a cam action, or by changing interchangeable pads or jaws.
The adjustable by screw types are limited in the range of pipe size that they can accomodate by the length of the jaws, are heavy and complex in construction. Their gripping action is limited and obtained by spreading the jaws round the half of a pipe against a spring, and are liable to slippage, particularly when operated in a difficult position or confined area.
The types with interchangeable jaws to accomodate varying pipe sizes are complex and expensive and require mechanical work to adjust.
Since, in the case of this invention, the grip applying members are driven towards each other around the pipe, by the mechanical action of interfacing gear forms, an automatic and powerful gripping action is provided that accepts a wide range of pipe sizes that is a greater size range than existing devices. The wrench can easily be "wrapped" around a pipe in close proximity to other obstructions and can be laid almost into a straight line for transporting or stowing.